Move error to spacy.cli.download

Add extra message for Jupyter sessions

spacy/cli/download.py

@@ -7,7 +7,13 @@ from wasabi import msg
 
 from .. import about
 from ..errors import OLD_MODEL_SHORTCUTS
-from ..util import get_minor_version, is_package, is_prerelease_version, run_command
+from ..util import (
+    get_minor_version,
+    is_in_jupyter,
+    is_package,
+    is_prerelease_version,
+    run_command,
+)
 from ._util import SDIST_SUFFIX, WHEEL_SUFFIX, Arg, Opt, app
 
 
@@ -78,6 +84,22 @@ def download(
         f"You can now load the package via spacy.load('{model_name}')",
     )
 
+    reload_deps_msg = (
+        "If you have one or more instances of the Python runtime executing "
+        "in the background, you'll need to restart them to correctly load "
+        "the dependencies of the newly downloaded model. "
+    )
+    if is_in_jupyter():
+        reload_deps_msg = (
+            f"{reload_deps_msg}This includes the current Jupyter session: "
+            "You can do this clicking on the 'Restart Kernel' button (or "
+            "'Restart Runtime' button in the case of Google Colab)"
+        )
+    msg.info(
+        "Reloading dependencies",
+        reload_deps_msg,
+    )
+
 
 def get_model_filename(model_name: str, version: str, sdist: bool = False) -> str:
     dl_tpl = "{m}-{v}/{m}-{v}{s}"

spacy/errors.py

@@ -229,10 +229,8 @@ class Errors(metaclass=ErrorsWithCodes):
             "If you're using a Transformer, make sure to install 'spacy-transformers'. "
             "If you're using a custom component, make sure you've added the "
             "decorator `@Language.component` (for function components) or "
-            "`@Language.factory` (for class components). If you installed the model "
-            "during the current Python/Jupyter session, you'll need to restart Python (or "
-            "reload your Jupyter notebook) to correctly load the dependencies.\n\n"
-            "Available factories: {opts}")
+            "`@Language.factory` (for class components).\n\nAvailable "
+            "factories: {opts}")
     E003 = ("Not a valid pipeline component. Expected callable, but "
             "got {component} (name: '{name}'). If you're using a custom "
             "component factory, double-check that it correctly returns your "